Thanks for reaching out to the Community, suzie12. I appreciate your detailed information.

I can certainly understand how an ability to merge projects into customer profiles could be useful and have submitted a suggestion about it as of today.

You can also submit your own feature requests while signed in.

Here's how:

1. Use the Gear icon, then go to Feedback.
2. Enter your suggestion(s) in the Have feedback? window.
3. If necessary, attach a file with your Camera icon.
4. Select Next.
   
   

Your feedback's definitely valuable to Intuit. It will be reviewed by our Product Development team and considered in future updates. You can stay up-to-date with the latest news about your product by reviewing Intuit's Product Updates webpage.

As a workaround, you can edit each transaction under your project and re-assign them to the appropriate customer. After doing so, you can delete your project.

I've also included a detailed resource about working with projects which may come in handy moving forward: Create and manage projects

Please feel welcome to send a reply if there's any additional questions. Have a lovely Tuesday!